blob: 9500e923bf38e81b779f62d1cca66ee0f7ee8172 [file] [log] [blame]
// System Management Mode support (on emulators)
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
// Copyright (C) 2006 Fabrice Bellard
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "pci.h" // PCIDevice
#include "util.h" // wbinvd
#include "config.h" // CONFIG_*
#include "ioport.h" // outb
asm(
".global smm_relocation_start\n"
".global smm_relocation_end\n"
".global smm_code_start\n"
".global smm_code_end\n"
" .code16\n"
/* code to relocate SMBASE to 0xa0000 */
"smm_relocation_start:\n"
" mov $0x38000 + 0x7efc, %ebx\n"
" addr32 mov (%ebx), %al\n" /* revision ID to see if x86_64 or x86 */
" cmp $0x64, %al\n"
" je 1f\n"
" mov $0x38000 + 0x7ef8, %ebx\n"
" jmp 2f\n"
"1:\n"
" mov $0x38000 + 0x7f00, %ebx\n"
"2:\n"
" movl $0xa0000, %eax\n"
" addr32 movl %eax, (%ebx)\n"
/* indicate to the BIOS that the SMM code was executed */
" mov $0x00, %al\n"
" movw $0xb3, %dx\n"
" outb %al, %dx\n"
" rsm\n"
"smm_relocation_end:\n"
/* minimal SMM code to enable or disable ACPI */
"smm_code_start:\n"
" movw $0xb2, %dx\n"
" inb %dx, %al\n"
" cmp $0xf0, %al\n"
" jne 1f\n"
/* ACPI disable */
" mov $" __stringify(BUILD_PM_IO_BASE) " + 0x04, %dx\n" /* PMCNTRL */
" inw %dx, %ax\n"
" andw $~1, %ax\n"
" outw %ax, %dx\n"
" jmp 2f\n"
"1:\n"
" cmp $0xf1, %al\n"
" jne 2f\n"
/* ACPI enable */
" mov $" __stringify(BUILD_PM_IO_BASE) " + 0x04, %dx\n" /* PMCNTRL */
" inw %dx, %ax\n"
" orw $1, %ax\n"
" outw %ax, %dx\n"
"2:\n"
" rsm\n"
"smm_code_end:\n"
" .code32\n"
);
extern u8 smm_relocation_start, smm_relocation_end;
extern u8 smm_code_start, smm_code_end;
void
smm_init()
{
if (!CONFIG_USE_SMM)
return;
// This code is hardcoded for PIIX4 Power Management device.
PCIDevice i440_pcidev, d;
int ret = pci_find_device(0x8086, 0x7113, 0, &d);
if (ret)
// Device not found
return;
ret = pci_find_device(0x8086, 0x1237, 0, &i440_pcidev);
if (ret)
return;
/* check if SMM init is already done */
u32 value = pci_config_readl(d, 0x58);
if (value & (1 << 25))
return;
/* copy the SMM relocation code */
memcpy((void *)0x38000, &smm_relocation_start,
&smm_relocation_end - &smm_relocation_start);
/* enable SMI generation when writing to the APMC register */
pci_config_writel(d, 0x58, value | (1 << 25));
/* init APM status port */
outb(0x01, 0xb3);
/* raise an SMI interrupt */
outb(0x00, 0xb2);
/* wait until SMM code executed */
while (inb(0xb3) != 0x00)
;
/* enable the SMM memory window */
pci_config_writeb(i440_pcidev, 0x72, 0x02 | 0x48);
/* copy the SMM code */
memcpy((void *)0xa8000, &smm_code_start,
&smm_code_end - &smm_code_start);
wbinvd();
/* close the SMM memory window and enable normal SMM */
pci_config_writeb(i440_pcidev, 0x72, 0x02 | 0x08);
}